This invention relates to a method for the manufacture of poly(etherimide)s. More particularly, it relates to a method for the manufacture of poly(etherimide)s which eliminates the need for nitration.
Polyetherimides are high heat engineering plastics having a variety of uses. The present commercial process for the synthesis of polyetherimides requires nitration of N-methylphthalimide to yield 4-nitro-N-methylphthalimide. 4-nitro-N-methylphthalimide is treated with the disodium salt of a bis(phenol) such as bisphenol A to yield a bisimide (I) having the following general structure: 
Bisimide (I) is then reacted with a phthalic anhydride in an exchange reaction to yield the dianhydride (II): Reaction of dianhydride (II) with a diamine results in polymerization to a poly (etherimide). Methods which improve or even eliminate any of the preceding steps would result in an improved synthesis of polyetherimides.